Current electronic-book-reading devices often fail to enable users to easily navigate through an electronic book (e-book). Consider, for example, three typical navigation interfaces common to current e-book-reading devices. In the first, the e-book-reading device enables a user to turn a page of an electronic book, such as with a tap or swiping gesture, one page at a time. While this permits navigation, it is slow and ponderous. In the second, the e-book-reading device enables a user to select a contents page from which to then select a chapter of the electronic book. After selecting the chapter, the e-book-reading device presents the first page of the selected chapter. While generally faster than page-by-page selection, this can also fail to enable the user to quickly find a desired page, such as when the user does not remember which chapter a desired page is within or when the user does not want to navigate to a chapter's first page, but instead to some portion of the chapter.
In the third navigation interface common to e-book-reading devices, the e-book-reading device enables the user to select a search term and then scan through various pages having the selected search term. This often fails the user, such as when the selected search term is too common to enable quick navigation or when the user does not remember terms on the desired page. Even in cases where using a search term enables the user to scan through a reasonable number of pages, the user still has to select the search term, often through a typing interface. Thus, even when fairly useful, navigation through search terms can be unacceptably slow and ponderous due to needing to select the term. Thus, current e-book-reading devices often fail to enable users to easily navigate an electronic book.